peterhillman

I added the 'join' logic to IlmThreadPool to address use-after-free issues (see PR #828). It's possible that's where this issue started to show up.

@lgritz well that's me off the hook then

I had a glance at the log but it now has disappeared. I believe it may have been `testBackwardCompatibility` that failed. You can run the test manually with `bin/IlmImfTest testBackwardCompatibility`...

Thanks for that - this is the error message from the build.log ``` Running testBackwardCompatibility Testing backward compatibility ERROR -- caught exception: v1.7 and current differences between '/var/tmp/IlmImfTest_CBTOGVNI/v1.7.test.planar.exr' & '/builddir/build/BUILD/openexr-2.5.3/OpenEXR/IlmImfTest/v1.7.test.planar.exr'...

@hobbes1069 thanks for that file. This appears to be a file from a different test than the one that reported failure in the build logs. `testTiledLineOrder` writes a file called...

Successful tests clean up files, so any files in the temporary directory are related to failed tests. My reading of the issue is that imf_test_copy.exr was left because `testTiledLineOrder` failed....

Can you provide your /var/tmp/IlmImfTest_HILEPYMX/v1.7.test.planar.exr? I tried a Raspberry Pi 4 Model B running 64 bit Ubuntu 20.10 and all tests passed. (Running through `ctest` did trigger a timeout, but...

Thanks! It seems like the zlib compressed data differs between aarch64 and x86_64 on fedora (though apparently not Ubuntu). I wonder if the compression level of Z_DEFAULT_COMPRESSION differs for some...

I'm not sure whether this is an issue. The file produced by `testBackwardCompatibility` does seem to be backward compatible, but the test inadvertently revealed binary differences between files produced by...

I've made some progress, getting Fedora Minimal working on a Raspberry Pi 4B, and reproduced the issue. The problem seems to be the way that the zlib library is built...